Comment on essd-2023-328 DOI Creative Commons

Опубликована: Сен. 26, 2023

Abstract. Diagnostic terrestrial biosphere models (TBMs) forced by remote sensing observations have been a principal tool to provide benchmarks on global gross primary productivity (GPP) and evapotranspiration (ET). However, these often estimate GPP ET at coarse daily or monthly step, hindering analysis of ecosystems dynamics the diurnal (hourly) scales, prescribe some essential parameters (i.e., Ball-Berry slope (m) maximum carboxylation rate 25 °C (Vcmax25)) as constant, inducing uncertainties in estimates ET. In this study, we present hourly estimation datasets 0.25° resolution from 2001 2020 simulated with widely used diagnostic TBM – Biosphere-atmosphere Exchange Process Simulator (BEPS). We employed eddy covariance machine learning approaches derive upscale seasonally varied m Vcmax25 for carbon water fluxes. The estimated are validated against flux observation, sensing, learning-based across multiple spatial temporal scales. correlation coefficients (R2) slopes between tower-measured modeled fluxes are: R2 = 0.83, regression 0.92 and, 0.72, 1.04 At scale, mean 137.78 ± 3.22 Pg C yr-1 (mean 1 SD) positive trend 0.53 yr-2 (p < 0.001), 89.03 0.82 × 103 km3 slight 0.10 0.001) 2020. pattern our agrees well other products, 0.77–0.85 0.74–0.90 ET, respectively. Overall, new dataset serves `handshake’ among process-based models, network, providing reliable long-term patterns facilitating studies related ecosystem functional properties, carbon, cycles. accumulated available https://doi.org/10.5281/zenodo.8240492 (Leng et al., 2023).

Язык: Английский

Deriving photosystem-level red chlorophyll fluorescence emission by combining leaf chlorophyll content and canopy far-red solar-induced fluorescence: Possibilities and challenges DOI
Linsheng Wu, Yongguang Zhang,

Zhaoying Zhang

и другие.

Remote Sensing of Environment, Год журнала: 2024, Номер 304, С. 114043 - 114043

Опубликована: Фев. 10, 2024

Язык: Английский

Процитировано

23
A gradient-based 3D nonlinear spectral model for providing components optical properties of mixed pixels in shortwave urban images DOI Creative Commons
Zhijun Zhen, Shengbo Chen, Nicolas Lauret

и другие.

Remote Sensing of Environment, Год журнала: 2025, Номер 321, С. 114657 - 114657

Опубликована: Фев. 28, 2025

Язык: Английский

Процитировано

2
A global estimate of multiecosystem photosynthesis losses under microplastic pollution DOI Creative Commons

Zhu Ruijie,

Zhaoying Zhang,

Naichi Zhang

и другие.

Proceedings of the National Academy of Sciences, Год журнала: 2025, Номер 122(11)

Опубликована: Март 10, 2025

Understanding how ecosystems respond to ubiquitous microplastic (MP) pollution is crucial for ensuring global food security. Here, we conduct a multiecosystem meta-analysis of 3,286 data points and reveal that MP exposure leads reduction in photosynthesis 7.05 12.12% terrestrial plants, marine algae, freshwater algae. These reductions align with those estimated by constructed machine learning model using current levels, showing reduces the chlorophyll content photoautotrophs 10.96 12.84%. Model estimates based on identified MP-photosynthesis nexus indicate annual losses 4.11 13.52% (109.73 360.87 MT·y −1 ) main crops 0.31 7.24% (147.52 3415.11 MT C·y aquatic net primary productivity induced MPs. Under scenarios efficient plastic mitigation, e.g., ~13% environmental MP-induced are decrease ~30%, avoiding loss 22.15 115.73 crop production 0.32 7.39 seafood production. findings underscore urgency integrating mitigation into hunger sustainability initiatives.

Язык: Английский

Процитировано

2
Global datasets of hourly carbon and water fluxes simulated using a satellite-based process model with dynamic parameterizations DOI Creative Commons
Jiye Leng, Jing M. Chen, Wenyu Li

и другие.

Earth system science data, Год журнала: 2024, Номер 16(3), С. 1283 - 1300

Опубликована: Март 13, 2024

Abstract. Diagnostic terrestrial biosphere models (TBMs) forced by remote sensing observations have been a principal tool for providing benchmarks on global gross primary productivity (GPP) and evapotranspiration (ET). However, these often estimate GPP ET at coarse daily or monthly steps, hindering analysis of ecosystem dynamics the diurnal (hourly) scales, prescribe some essential parameters (i.e., Ball–Berry slope (m) maximum carboxylation rate 25 °C (Vcmax25)) as constant, inducing uncertainties in estimates ET. In this study, we present hourly estimations datasets 0.25° resolution from 2001 to 2020 simulated with widely used diagnostic TBM – Biosphere–atmosphere Exchange Process Simulator (BEPS). We employed eddy covariance machine learning approaches derive upscale seasonally varied m Vcmax25 carbon water fluxes. The estimated are validated against flux observations, sensing, learning-based across multiple spatial temporal scales. correlation coefficients (R2) slopes between tower-measured modeled fluxes R2=0.83, regression =0.92 GPP, R2=0.72, =1.04 At scale, mean 137.78±3.22 Pg C yr−1 (mean ± 1 SD) positive trend 0.53 yr−2 (p<0.001), an 89.03±0.82×103 km3 slight 0.10×103 (p<0.001) 2020. pattern our agrees well other products, R2=0.77–0.85 R2=0.74–0.90 ET, respectively. Overall, new dataset serves “handshake” among process-based models, network, reliable long-term patterns facilitating studies related functional properties, carbon, cycles. available https://doi.org/10.57760/sciencedb.ecodb.00163 (Leng et al., 2023a) accumulated https://doi.org/10.57760/sciencedb.ecodb.00165 2023b).

Язык: Английский

Процитировано

9
Seasonal variation in the relationship between leaf chlorophyll content and photosynthetic capacity DOI Creative Commons
Liyao Yu, Xiangzhong Luo, Holly Croft

и другие.

Plant Cell & Environment, Год журнала: 2024, Номер 47(10), С. 3953 - 3965

Опубликована: Июнь 7, 2024

Abstract Accurate estimation of photosynthesis is crucial for ecosystem carbon cycle modelling. Previous studies have established an empirical relationship between photosynthetic capacity (maximum carboxylation rate, V cmax ; maximum electron transport J max ) and leaf chlorophyll (Chl) content to infer global capacity. However, the basis Chl‐V remains unclear, which further evidenced by temporal variations in relationship. Using multiple years observations four deciduous tree species, we found that acclimate photosynthetically active radiation faster (4–8 weeks) than Chl (10–12 weeks). This mismatch scales causes seasonality ‐Chl To account mismatch, used a fluorescence parameter (quantum yield Photosystem II, Φ(II)) tighten Φ(II) × correlated with ( r 2 = 0.74 0.72 respectively) better only 0.7 0.6 respectively). It indicates accounts short‐term adjustment light, was not captured Chl. Our study advances our understanding ecophysiological how from fluorescence, guides large‐scale simulations using remote sensing.

Язык: Английский

Процитировано

8
Comparative assessment of leaf photosynthetic capacity datasets for estimating terrestrial gross primary productivity DOI
Mingzhu Xu, Jing M. Chen, Yihong Liu

и другие.

The Science of The Total Environment, Год журнала: 2024, Номер 926, С. 171400 - 171400

Опубликована: Март 8, 2024

Язык: Английский

Процитировано

3
Intercomparison and validation of five existing leaf chlorophyll content products over China DOI Creative Commons
Xiaohan Wang, Jing Li, Hu Zhang

и другие.

International Journal of Applied Earth Observation and Geoinformation, Год журнала: 2024, Номер 130, С. 103930 - 103930

Опубликована: Май 29, 2024

Leaf chlorophyll content (LCC) is crucial in plant physiology and ecological research. Although several LCC products have recently been generated at a regional or global scale, understanding their accuracy still concern the scientific community. We intercompared analyzed five existing (MuSyQ LCC, MODIS MERIS GLCC, GLOBMAP LCC) over China terms of spatial continuity spatiotemporal consistency seven functional types. The 2011 2019 were used this study. Research findings indicate (1) 30 m-resolution MuSyQ has highest compared to field cropland grassland types, with an RMSE 19.5 μg/cm2, while product demonstrates more robust fit measured R2 0.341. (2) Interpolation lower resolution e.g. generally improves continuity. non-interpolated m exhibits good due its high resolution. lowest found shrubs for all products. (3) demonstrate overall exhibit correlation sites. temporal deciduous forests, evergreen grasslands, most exhibited among needleleaved forest, followed by forest grassland. research are essential improving leaf inversion algorithms better use land surface models.

Язык: Английский

Процитировано

3
Optimized Gross Primary Productivity Over the Croplands Within the BEPS Particle Filtering Data Assimilation System (BEPS_PF v1.0) DOI Creative Commons
Xiuli Xing, Mousong Wu, Huajie Zhu

и другие.

Journal of Advances in Modeling Earth Systems, Год журнала: 2025, Номер 17(1)

Опубликована: Янв. 1, 2025

Abstract Agricultural ecosystems play an important role in modulating the global carbon balance by taking up atmospheric dioxide, while large differences and uncertainties exist estimated crop gross primary productivity (GPP) terrestrial ecosystem models (TEMs). With aim of reducing parameter uncertainty TEMs for GPP simulation, we developed a particle filtering data assimilation (DA) system based on model BEPS (Biosphere Exchange Process Simulator), that is, BEPS_PF (v1.0). We investigated feasibility multiple parameters optimization across typical crops (wheat, rice, soybean corn) over 32 cropland eddy covariance sites globally. DA, average R 2 between observed at hourly scale has been efficiently improved 0.36 root mean square error reduced 0.18 gC m −2 hr −1 . The DA successfully corrected from irrigated croplands which was severely underestimated model's prior parameters. found maximum carboxylation rate 25°C ( V cmax25 ) as well leaf nitrogen content N were co‐varied with strong seasonal variations. optimized showed among different types ranges 27.07–62.95, 42.17–93.32, 31.89–105.81, 38.34–89.29 μmol s corn, soybean, wheat, rice respectively. demonstrated is efficient tool optimizing processes ecosystems, satellite it can be extended to regional scales more accurate estimation fluxes.

Язык: Английский

Процитировано

0
Application of Simultaneous Active and Passive Fluorescence Observations: Extending a Fluorescence-Based qL Estimation Model DOI Creative Commons

Chenhui Guo,

Zhunqiao Liu, Xiaoliang Lü

и другие.

Sensors, Год журнала: 2025, Номер 25(6), С. 1700 - 1700

Опубликована: Март 9, 2025

The fraction of open Photosystem II (PSII) reaction centers (qL) is critical for connecting broadband PSII fluorescence (ChlFPSII) with the actual electron transport from to I. Accurately estimating qL fundamental determining ChlFPSII, which, in turn, vital mechanistically rate and photosynthetic CO2 assimilation. Chlorophyll provides direct physiological insights, offering a robust foundation estimation. However, uncertainties ChlFPSII–qL relationship across different plant functional types (PFTs) limit its broader application at large spatial scales. To address this issue, we developed leaf-level instrument capable simultaneously measuring actively passively induced chlorophyll fluorescence. Using system, measured light response, temperature response curves 52 species representing seven PFTs. Our findings reveal following: (1) strong linear correlation between ChlFPSII derived that (R2 = 0.85), (2) while parameters varied among PFTs, reliably modeled within each PFT, R2 ranging 0.85 0.96. This study establishes quantitative relationships various PFTs by utilizing calculate ChlFPSII. results demonstrate potential remotely sensed data estimate strengthen use fluorescence-based approaches mechanistic GPP estimation

Язык: Английский

Процитировано

0
Solar Induced Chlorophyll Fluorescence: Origins and Applications, Relation to Photosynthesis and Retrieval DOI
Yongguang Zhang, Zhaoying Zhang

Elsevier eBooks, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

Язык: Английский

Процитировано

0